Its not jet-related but... I think there's an old thread in the RCU SPAD forum that shows a group of guys playing target practice with a bunch of SPADs and an anti-aircraft gun. The planes were pretty hard to hit apparently.

A friend at work is designing a 2-axis turret with a paint ball gun. He's got stepper motors on each axis driven by electronics out of an automated printing machine (what we make for a living), and a video camera to track the target. He's a firmware guy... He says he's got the software working with a primitive 'prediction' routine to interpolate where the gun should shoot based on the trajectory of the aircraft, knowing that the paintball will take some time to get there. If the aircraft radically changes course the software is suppose to compensate and keep firing. Hopefully he's got it ready for this summer's combat meets... Adding a some surface-to-air fire would make a 6 or 8-man combat round that much better!

Kelly W